The Food and Drug Administration has no definition of "natural," but does not object to manufacturers using it provided the item does not contain added color, artificial flavors or synthetic substances. Yet, as Consumer Reports points out, those ingredients are found in many "natural" products.

The group has launched a campaign to ban the word "natural" on labels, following a survey that showed that nearly 80 percent of the 1,000 people polled believe that the use of the term should define food without pesticides, artificial ingredients or genetically modified organisms.

"Our findings show consumers expect much more from the 'natural' food label," said Urvashi Rangan, executive director of Consumer Reports Food Safety and Sustainability Center.